There's probably someone with enough time and resources to screw up the blockchain again. This is the big and unsolvable problem that Ethereum designed upon itself: A platform in which people can develop trash like Cryptokitties to bloat up the blockchain.

Ethereum is broken by design and it will not end well. It's going to collapse someday. I hate to say that but I think it's what will happen. And im not convinced that any of these so called scaling solutions will save it as well.

Stick to Bitcoin if you want to hold crypto long term, everything else is too risky. Most likely all other systems have systemic flaws on their designs.